This project is designed to investigate the relation of childhood nutrition to breast cancer risk factors, including age at menarche, adult height, weight, and fatness. Secondary purposes include tracking the development of overweight and obesity from birth through young adulthood, identification of possible "sensitive" or high-risk periods (wit respect to obesity) in childhood and, more important, to identify the contribution of diet to the development of childhood and adult obesity. Detailed anthropometric data (height, weight, skinfold thickness, etc.) and demographic characteristics available from a computer data base from the Fels Study and the Division of Human Biology of the Wright State School of Medicine included up to 18 annual dietary and anthropometric assessments for 106 girls. Calorie, macro- and micronutrient data were linked to the existing anthropometry computer file, including later adult height and weight. Nutrient composition has been calculated using the latest version of the USDA Handbook series. Nutrients include the following: total energy (kilocalories); total fat, protein, and carbohydrat saturated, polyunsaturated, and monounsaturated fat; cholesterol; dietary fiber; and vitamins and minerals (from food and supplementary sources). This study is being conducted collaboratively with scientists at the Wright State School of Medicine in Yellow Springs, Ohio. Data analysis is currently underway.